Jean pierke serve



(No Model.)

J. P. SERVE.

MECHANISM FOR MAKING RIBBED TUBES 438,025.

Patented Oct. '7, 1890.

UNITED ST TES PATENT OFFICE.

JEAN PIERRE SERVE,OF GIVORS, FRANCE.

MECHANISM FOR MAKING RIBBED TUBES.

SPECIFICATION forming part of Letters Patent No. 438,025, dated October 7, 1890.

Application filed August '7, 1889. Serial No. 320,045- (No model.) Patented in Belgium April 23, 1888, No. 85,937; in England May 26,1888,N0.7,709; in France February 20, 1889, No. 196,697, and in Italy July 1,1889, No. 25,747.

To all whom it may concern:

Be it known that I, JEAN PIERRE SERVE, manufacturer, a citizen of the Republic of France, and a resident of Givors, Department of Rhone,France, have invented certain new and useful Improvements Relating to the Manufacture of Boiler and other Tubes and to Apparatus Therefor, (for which I have obtained patents in the following countries: in France, N 0. 196,897, dated February 20, 1889; in Italy, No. 25,747, dated July 1, 1889; in Belgium, No. 85,937, dated April 23, 1888, and in Great Britain,No. 7,709, dated May26, 1888,) of which the following is a specification, reference being had to the accompanying drawings.

In the United States Letters Patent No. 349,060, granted to me on the 14th of September, 1886, I claimed a system of tubes for boilers, condensers, &c., provided with ribs for the purpose of increasing their power of transmission of either heat or cold.

The present invention relates to improved means whereby the said ribbed tubes are made of iron or steel and welded.

' In manufacturing ribbed tubes of either iron or steel by a welding process a plate is first taken for a starting-piece or blank, which has been obtained direct by hammering or casting or by drawing an ingot of rectangular or other sect-ion of a thickness at least equal to that of the blank when completed, including the depth of the ribs.

It is unnecessary to further dwell upon the process of manufacture of the said blank obtained by hammering, by casting, or by a preliminary roughing-down or rolling operation in a suitable rolling-mill. It should only be borne in mind that such blank may be provided with projections on one side and be fiat on the other or have projections on both sides. It is thus obtained either by hammering or direct by casting or by being subjected to the action of a roughing-down mill, the upper roll of which is alone provided with grooves, while the lower roll is smooth, or in which both the upper and the lower rolls are grooved or fluted. I

The blanks being thus obtained by wellknown means, it was necessary to roll them up into the shape of tubes and to Weld the edges, which operations form the object of the invention herein described.

In the accompanying drawings, Figure 1 is a cross-section of the blank or plate provided with projections on both sides a and b. Fig. 2 is a cross-section of the blank or plate pro vided with projections a on one side and with a flat portion 1) on the other. Fig. 3 is avertical section of the finishing-mill into which the blank is introduced.

The grooves in this rolling-millbecome nar rower in each successive pair of rolls, each pair of rolls corresponding to one pass, and the last pair delivering the plate or blank in a-condition enabling it to be rolled up into the form of a tube, and provided with ribs on one of its surfaces, such as it is desired the tube should have, while the other surface is smooth.

In the drawings I have supposed the rolling-mill to be divided into three sections A B 0, corresponding to the three passes. 41. is a specimen, on an enlarged scale, of the form assumed by the blank after passing through section A of the rolling-mill. Fig. 5 is a view, also on an enlarged scale, of the shape assumed by the blank after its passage through section B of the rolling-mill. Fig. 6 is an enlarged view of the blank when finishedr'. 6., upon issuing from section 0 of the rolling-mill, when it only requires to be rolled up into the shape of a tube and its edges welded together.

\rVe have only in this instance considered the case when the blank is provided with projections on both sides. The same series of operations, however, is also to be gone through in the case when the blank is only provided With projections on one side and left smooth on the other, in which case the lower rolls of the rolling-mill are smooth instead of being grooved or fluted. In either case at the end of the operation the blank will be found to be in a condition adapting it to be rolled up and welded, as shown in Fig. 6.

Fig.

Fig. 7 is a longitudinal section of a tube with inner ribs placed upon a mandrel and submitted to the action of the rolls of a tube rolling mill intended to effect the welding of the edges. Fig. 8 is a cross-section of such finished ribbed tube.

I desire it to be understood that I hereby disclaim any right as regards the method of forming the blanks hereinbefore referred to, but that I only claim the formation of ribbed plates and the process of welding their edges. This being understood, I shall now proceed to describe the manner in which those operations are carried into effect.

To obtain a tube with inner longitudinal ribs, the depth of which enables them to project inwardly a sufficient distance for the transmission of the greatest part of the heat contained in the gases or vapors passing through such tubes, as illustrated in Fig. 8, the blank, as shown in Figs. 1 and 2, is first obtained by hammering, casting, or rolling. This blank or plate is made thicker in the portions where the ribs are to be formed, smaller projections or protuberances I) being formed on one side of the plate than the projections or protuberances a formed on the other side. In determining the size of these projections or protuberances care should be taken that they consist of a sufficient amount of metal to form ready ribs without its being necessary to borrow the metal or any part of such metal from the body of the plate. This plate is then submitted to the action of a rolling-mill, Fig. 3, the upper rolls of which, corresponding to groove (1, are provided with grooves getting narrower in each succeeding pair of rolls, so that the projections may become gradually thinner as the'plate is elongated by the action of the rolls. On the other hand, the grooves of the lower roll, corresponding to projections I), constantly diminish in depth and finally disappear altogether at or near the last pass of the plate between the rolls, the metal contained in these pro tuberances being designed to serve for the formation of the ribs of the other side of the plate.

During the rolling operation the thickness of both the plate and projections is gradually reduced, so as to give the plate the shape represented'in Fig. 6. By these successive reductions projections a diminish in thickness as the plate is elongated, the metal used for the ribs being provided by projections a and b, Fig. 1, and the metal employed for forming the body of the plate being supplied by the initial plate or blank wherewith the operations are commenced. These counter proj ections or protuberances b, destined to disappear, are not absolutely necessary, and the plate shown in Fig. 6 may, if required, be obtained by employing a smooth lower roll throughout the operation. In that case the plate shown in Fig. 2 should be used as a blank.

The ribbed plate being thus obtained, one end of the same is slightly bent by means of a hammer. Then the plate is made to pass while hot through a species of funnel-shaped draw-plate, whereby it is given a cylindrical shape, its edges being thus caused to meet or overlap in position to be welded together and form a complete tube. This longitudinal junction of both edges of the rolled-up plate may be effected by bending the longitudinal edges at right angles to the surface of the plate, so that the edges thus turned up and bolted or otherwise fastened together form one of the ribs of the tube, while the projecting portions areconnectedbymeansoftherolling-mill. The junction may also be performed in the smooth portion between the ribs by causing the edges of the rolled-up tube to meet or overlap and welding them together by means of the tuberolling-mill or of the draw-plate, the tube being heated before or during the operation by means of a blow-pipe or in any other convenient manner-for example, by electricit-yi. e., by the process termed electric welding.

To weld together the longitudinal edges of the inner ribs by means of a rolling-mill, I make use of the following contrivance, illustrated by Fig. 7: In this arrangement the welding process is based upon the employment of two grooved rolls HL. In this case the heated tube is supported at the point where it passes between the rolls by a beveled mandrel F, provided with grooves f, admitting of the passage of ribs a and kept in position by rod G. This mandrel F is, as shown, provided with grooves widened at the other edges i. a, at the entrance. At the same time ribs f are reduced in height, so as to facilitate the insertion of the tube into the mandrel. The mandrel should also be capable of turning freely upon rod G, and thereby be adapted to yield to the action of the ribs of the tube, which guide it into the proper position, so that it may oppose no objectionable resistance at the moment when the tube is inserted into the grooves of the roll and when the rolls act upon this tube to weld its edges together.

WVhat I claim is- 1. The ribbed plate having its edges fitted together, in combination with a grooved tapering mandrel with which the ribs of the plate engage and a rod for holding the mandrel in position, substantially as described.

2. The ribbed plate having its edges fitted together, in combination with the grooved tapering mandrel with which the ribs of the plate engage, a rod for holding themandrel in position, and grooved or fluted cylinders for acting on the ribbed plate to weld its edges, substantially as described.

In testimony whereof I have hereunto signed my name in the presence of two subscribing witnesses.

JEAN PIERRE SERVE.

Witnesses:

GEORGES FREYDIER DUBREUL, XAVIER J ANICOT.

ICS 

